Method for detecting blood chamber pressure drop of HD single-pump machine and HD single-pump machine

Abstract

The invention relates to an HD single-pump machine blood chamber pressure drop detection method and an HD single-pump machine, the HD single-pump machine comprises a dialyzer, a dialysate loop and a blood loop, the dialyzer comprises a semi-permeable membrane, the dialysate loop flows through the outer side of the semi-permeable membrane, the blood chamber is arranged on the inner side of the semi-permeable membrane, and the blood loop flows through the blood chamber. The dialysate pressure value on the outer side of the semi-permeable membrane is made to be equal to the blood chamber pressure value on the inner side of the semi-permeable membrane; the pressure value of the liquid return end of the dialysate loop, the pressure value of the blood chamber outlet end, the dialysis flow and the dialysate pressure difference coefficient are obtained; based on the liquid return end pressure value, the blood chamber outlet end pressure value, the dialysis flow and the dialysate pressure difference coefficient, blood chamber pressure drop is obtained through calculation, and the blood chamber pressure drop serves as a detection result. Detection of the blood chamber pressure drop can be completed only by using existing equipment conditions, a pressure sensor does not need to be additionally arranged at the inlet end of the dialyzer blood chamber, and outstanding practicability is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of hemodialysis, and in particular to a method for detecting blood chamber pressure drop of a HD single-pump machine and a HD single-pump machine. Background Art

[0002] The hemodialysis system is a renal replacement therapy system that draws the patient's blood out of the body and purifies the patient's blood through a dialyzer containing a semipermeable membrane before transporting it back into the body. It uses the concentration gradient characteristics, osmotic pressure gradient characteristics, water pressure gradient characteristics and the characteristics of the semipermeable membrane itself when the blood and dialysate flow between the two layers of the semipermeable membrane to remove metabolic waste and excess water in the blood through the principles of diffusion, convection and adsorption, and solve the electrolyte imbalance and acid-base imbalance of the patient's blood.

[0003] At present, different types of hemodialysis methods and instruments are required for patients with different conditions, including hemodialysis (HD) using a single pump machine, which is mainly used to remove small molecule toxins and is suitable for the early stage of hemodialysis; hemodiafiltration (HDF) using a dual pump machine, which mainly removes medium molecule toxins and is suitable for the mid-stage of hemodialysis. Since the HDF dual pump machine is less effective in removing small molecule toxins than the HD single pump machine, and the HDF dual pump machine and the HD single pump machine have different corresponding medical treatment courses, the two cannot be used interchangeably.

[0004] The existing HDF dual-pump machine has a pressure sensor for detecting the inlet end of the dialyzer blood chamber and a venous pressure sensor for detecting the outlet end of the dialyzer blood chamber. It can detect the pressure drop of the dialyzer blood chamber more conveniently by comparing the pressure value of the blood chamber inlet end with the pressure value of the blood chamber outlet end. The blood chamber pressure drop refers to the difference in blood pressure inside and outside the blood chamber when the hemodialysis equipment is in normal working condition. In layman's terms, it refers to the resistance that blood needs to overcome when passing through the hemodialysis equipment during the dialysis process, which can also be understood as the resistance inside the dialyzer. The size of the blood chamber pressure drop directly affects the dialysis effect of the dialyzer and the impact on the patient during the dialysis process. However, the existing HD single-pump machine does not have a pressure sensor for detecting the inlet end of the dialyzer blood chamber. Therefore, the existing HD single-pump machine cannot detect the pressure drop of the dialyzer blood chamber, resulting in medical staff being unable to detect the coagulation and blood permeability of patients during hemodialysis (HD) through the blood chamber pressure drop. Summary of the invention

[0005] The purpose of the present invention is to provide a method for detecting blood chamber pressure drop of a HD single pump machine, so as to solve the technical problem that the HD single pump machine cannot detect the blood chamber pressure drop due to the lack of a pressure sensor for detecting the blood chamber inlet end of the dialyzer.

[0006] In order to achieve the above object, the first aspect of the present invention provides a method for detecting blood chamber pressure drop of a HD single pump machine, wherein the HD single pump machine comprises a dialyzer, a dialysate circuit and a blood circuit, wherein the dialyzer comprises a semipermeable membrane, wherein the dialysate circuit flows through the outer side of the semipermeable membrane, wherein the inner side of the semipermeable membrane is a blood chamber, wherein the blood circuit flows through the blood chamber, and the method comprises the following steps:

[0007] When the dialyzer performs hemodialysis, the dialysate pressure value on the outside of the semipermeable membrane is made equal to the blood chamber pressure value on the inside of the semipermeable membrane; the return end pressure value of the dialysate loop, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient are obtained; the blood chamber pressure drop is calculated based on the return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient, and the blood chamber pressure drop is used as the detection result.

[0008] The above-mentioned method for detecting blood chamber pressure drop of a single-pump HD machine is to make the dialysate pressure value on the outside of the semipermeable membrane equal to the blood chamber pressure value on the inside of the semipermeable membrane when the single-pump dialyzer performs hemodialysis. On the basis of this condition, the present invention obtains the return end pressure value, dialysis flow rate and dialysate pressure difference coefficient of the dialysate circuit on the outside of the semipermeable membrane, and obtains the pressure value of the blood chamber outlet end on the inside of the semipermeable membrane, and indirectly obtains the blood chamber pressure drop on the inside of the semipermeable membrane using the data on the outside of the semipermeable membrane, so that when the single-pump machine lacks a pressure sensor for detecting the blood chamber inlet end and cannot obtain the pressure value at the blood chamber inlet end, the blood chamber pressure drop is detected, solving the technical problem that the existing HD single-pump machine cannot detect the blood chamber pressure drop. In addition, the present invention can complete the detection of the blood chamber pressure drop by only using the existing equipment conditions of the HD single-pump machine, and does not need to additionally install a pressure sensor at the blood chamber inlet end of the dialyzer, which is easy to promote and use in this field and has outstanding practicality.

[0009] It should be noted that, since a pressure sensor is additionally installed at the inlet of the blood chamber of the dialyzer of the HD single-pump machine, obtaining the pressure value at the inlet of the blood chamber faces technical difficulties in actual operation, which will bring about a bad technical effect. To further explain, this application provides a supplementary explanation of the difficulties faced by the technical means of "additionally installing a pressure sensor at the inlet of the blood chamber of the dialyzer of the HD single-pump machine" in actual operation through the following content.

[0010] First of all, it is worth noting that in the existing HD single-pump machine, the dialyzer blood chamber inlet also has a blood pump, which is used to adjust the pressure in the blood circuit and promote the blood to circulate in the blood circuit. Specifically, after the human arterial blood flows into the blood circuit through the arterial puncture needle, it is pressurized by the blood pump and pumped into the dialyzer blood chamber from the blood chamber inlet. After the hemodialysis process is completed in the dialyzer blood chamber, it flows out from the blood chamber outlet and returns to the human vein through the blood circuit and the venous puncture needle. The mechanical movement of the blood pump pumping blood fluid will introduce periodic fluctuations and vibrations. The additional installation of a pressure sensor at the blood chamber inlet will be disturbed by the mechanical movement of the blood pump, affecting the stable measurement of the pressure sensor and causing errors in the measured data. If the pressure sensor works in the above environment for a long time, its service life will be affected and even damaged.

[0011] Secondly, after adding a pressure sensor to the blood chamber inlet of the existing HD single pump machine, the connection structure of the corresponding blood pipeline needs to be redesigned, which may change the fluid dynamics of blood flowing in the blood circuit and produce a bad technical effect on the hemodialysis function of the HD single pump machine. In addition, the additional pressure sensor needs to be calibrated and maintained regularly, which increases the complexity of the equipment and reduces the practicality of the HD single pump machine itself.

[0012] Finally, since the existing HDF dual-pump machine is equipped with an additional blood pump, in addition to a blood pump used to promote the circulation of blood in the blood circuit, another blood pump is also required to control the injection of replacement fluid into the blood circuit, so that the HDF dual-pump machine has a larger equipment layout and a blood circuit design with longer pipelines than the HD single-pump machine, and can carry the pressure sensor at the entrance of the blood chamber. However, since the existing HD single-pump machine only needs to use one blood pump, its overall structure is more streamlined than that of the HDF dual-pump machine, and its pipeline design is more centralized, and there are not many locations to carry an additional pressure sensor at the entrance of the blood chamber. If an additional pressure sensor is forcibly installed at the entrance of the blood chamber of the existing HD single-pump dialyzer, it may also destroy the streamlined structure of the HD single-pump machine itself, which will have a negative impact on the technical effects of the HD single-pump machine's simple structure and easy operation, making the HD single-pump machine no longer suitable for the needs of the initial hemodialysis treatment.

[0013] It should be understood that in the field of medical equipment technology, the positive technical effects of hemodialysis equipment are not simply determined by factors such as the size of the equipment or the number of blood pumps in the equipment. For patients with different conditions and different courses of treatment, the corresponding hemodialysis methods and instruments need to be used correctly in order for the medical equipment to produce the corresponding technical effects. Specifically, the HDF dual-pump machine is suitable for hemodialysis filtration treatment, which mainly removes middle-molecular toxins and is used in the middle and late stages of hemodialysis. Although the HDF dual-pump machine has an additional blood pump and pressure sensor compared to the HD single-pump machine, for patients in the initial course of hemodialysis, the HDF dual-pump machine has a poorer effect on the removal of small molecule toxins than the HD single-pump machine, and the complex functionality of the HDF dual-pump machine may bring additional risks to patients in the initial course of hemodialysis. For example, the HDF dual blood pump brings too high a blood flow rate for patients in this period, and the dual-pump machine injects replacement fluid into the blood circuit, which may also cause an imbalance in body fluid management for patients in this period. Therefore, even though the HDF dual-pump machine has a pressure sensor at the inlet of the dialyzer blood chamber and a venous pressure sensor at the outlet of the dialyzer blood chamber, and can more conveniently detect the pressure drop in the dialyzer blood chamber by comparing the pressure value at the inlet of the blood chamber with the pressure value at the outlet of the blood chamber, it cannot replace the HD single-pump machine for the initial course of hemodialysis to provide hemodialysis treatment to patients.

[0014] In summary, the existing HD single pump machine is irreplaceable for the medical treatment it is applicable to. Adding an additional pressure sensor to the existing HD single pump machine is not only difficult to implement, but also has poor results. It may also destroy the original streamlined structure of the existing HD single pump machine, resulting in poor technical effects. On this basis, the present invention can complete the detection of blood chamber pressure drop using only the existing equipment conditions of the HD single pump machine, and does not require the additional installation of a pressure sensor at the inlet end of the dialyzer blood chamber. It is easy to promote and use in this field and has outstanding practicality.

[0015] In a possible implementation, the specific calculation formula for obtaining the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient is the following formula 1:

[0016] PB = (PDo + PDo + K*F d ) - 2PV (Formula 1)

[0017] Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, PDo is the pressure value at the return end, K is the pressure difference coefficient of the dialysate, and F d is the dialysis flow rate.

[0018] It should be noted that the blood chamber pressure drop specifically refers to the blood chamber inlet pressure value minus the blood chamber outlet pressure value. In the medical field, the blood chamber inlet pressure is also called the filter pre-pressure, and the blood chamber outlet pressure value is also called the venous pressure. Therefore, the dialyzer blood chamber pressure drop can also be described as equal to the filter pre-pressure minus the venous pressure, which can be expressed by the following formula 2:

[0019] PB = PA - PV (Formula 2)

[0020] Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, and PA is the pressure value at the inlet of the blood chamber.

[0021] For the blood circuit flowing through the blood chamber, since there is resistance in the blood circuit, the pressure of blood flowing out of the dialyzer blood chamber will be lower than the pressure when it flows into the dialyzer blood chamber, that is, the pressure at the blood chamber outlet is lower than the pressure at the blood chamber inlet, and this pressure drop process is a linear drop process. Therefore, the blood chamber pressure value inside the dialyzer semipermeable membrane is equal to the average of the blood chamber inlet pressure value and the blood chamber outlet pressure value, which can be expressed as the following formula 3:

[0022] Pb = (PA + PV) / 2 (Formula 3)

[0023] Wherein, Pb is the pressure value of the blood chamber, PA is the pressure value at the inlet end of the blood chamber, and PV is the pressure value at the outlet end of the blood chamber.

[0024] It should also be noted that in the medical field, the end of the dialysate loop in the HD single pump machine that flows into the dialyzer has a liquid supply valve, which can be called the liquid supply end, and the end of the dialysate loop that flows out of the dialyzer has a liquid return valve, which can be called the liquid return end. For the pressure value of the liquid supply end and the pressure value of the liquid return end, there is a mathematical relationship as shown in the following formula 4:

[0025] Pn = PDi - PDo = K*F d (Formula 4)

[0026] Wherein, Pn is the pressure difference between the dialysate flowing into the dialyzer and flowing out of the dialyzer, that is, the pressure difference between the supply end and the return end, PDi is the pressure value at the supply end, PDo is the pressure value at the return end, K is the dialysate pressure difference coefficient, F d is the dialysis flow rate.

[0027] Similarly, for the dialysate loop flowing through the outside of the semipermeable membrane, since there is also resistance in the process of dialysate flowing in the dialysate loop, the pressure of the dialysate when it flows out of the dialyzer will be lower than the pressure when it flows into the dialyzer, that is, the pressure at the return end of the dialysate loop is lower than the pressure at the supply end of the dialysate loop, and this pressure drop process is a linear drop process. Therefore, the dialysate pressure value outside the dialyzer semipermeable membrane is equal to the average of the pressure value at the supply end and the pressure value at the return end, which can be expressed as the following formula 5:

[0028] Pd = (PDi + PDo) / 2 (Formula 5)

[0029] Among them, Pd is the dialysate pressure value outside the semipermeable membrane, PDi is the pressure value at the supply end, and PDo is the pressure value at the return end.

[0030] In this implementation, by making the dialysate pressure value Pd outside the semipermeable membrane equal to the blood chamber pressure value Pb inside the semipermeable membrane, the physical quantities in the HD single pump machine at this moment have the physical relationship described in the following formula 6:

[0031] Pb = ( PA + PV ) / 2 = Pd = ( PDi + PDo ) / 2 (Equation 6)

[0032] Among them, Pb is the blood chamber pressure value, PA is the blood chamber inlet pressure value, PV is the blood chamber outlet pressure value, Pd is the dialysate pressure value outside the semipermeable membrane, PDi is the pressure value at the supply end, and PDo is the pressure value at the return end. On this basis, the physical relationship of Formula 6, Formula 4 and Formula 2 is combined to obtain the physical calculation formula shown in Formula 1. Through the above technical means, this implementation method does not need to obtain the blood chamber inlet pressure value to detect the blood chamber pressure drop at the current moment, which solves the technical problem that the existing HD single pump machine cannot detect the blood chamber pressure drop, and does not need to install an additional pressure sensor at the dialyzer blood chamber inlet, which is easy to promote and use in this field.

[0033] In a possible implementation, the HD single-pump machine also includes an ultrafiltration pump, which is located at the return end of the dialysate circuit. When the dialyzer performs hemodialysis, the dialysate pressure value on the outside of the semipermeable membrane is made equal to the blood chamber pressure value on the inside of the semipermeable membrane, including: controlling the ultrafiltration pump to pause operation, so that the dialysate pressure value on the outside of the semipermeable membrane is equal to the blood chamber pressure value on the inside of the semipermeable membrane.

[0034] In this implementation, the ultrafiltration pump is used to adjust the pressure in the dialysate circuit and drive the dialysate to circulate in the circuit. When the ultrafiltration pump is suspended, the dialysate pressure in the dialysate circuit is no longer disturbed by the additional pressure applied by the ultrafiltration pump, but is only affected by the static pressure. At this time, based on the physical properties of the semipermeable membrane, the dialysate pressure outside the semipermeable membrane will gradually converge with the blood chamber pressure inside the semipermeable membrane, and finally achieve a dynamic pressure balance between the inside and outside of the semipermeable membrane, so that the dialysate pressure value outside the semipermeable membrane is equal to the blood chamber pressure value inside the semipermeable membrane.

[0035] In a possible implementation, the blood chamber pressure drop is calculated based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient, and after the blood chamber pressure drop is used as the detection result, it also includes: controlling the ultrafiltration pump to resume operation so that the dialyzer continues to perform hemodialysis.

[0036] In this implementation, after calculating the current blood chamber pressure drop as the detection result, the ultrafiltration pump is restored to operate, thereby pressurizing the dialysate in the dialysate circuit, pushing the dialysate to circulate in the dialysate circuit, thereby allowing the dialyzer to continue hemodialysis.

[0037] The second aspect of the present invention provides an HD single pump machine, comprising a dialyzer, a dialysate circuit, a blood circuit, a detection module and a main control module, wherein: the dialyzer is used for hemodialysis, and comprises a semipermeable membrane, the dialysate circuit flows through the outside of the semipermeable membrane, the inside of the semipermeable membrane is a blood chamber, and the blood circuit flows through the blood chamber; the detection module is electrically connected to the main control module, and is used to obtain the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient of the dialysate circuit and send them to the main control module; the main control module is used to make the dialysate pressure value on the outside of the semipermeable membrane equal to the blood chamber pressure value on the inside of the semipermeable membrane, and then calculate the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient.

[0038] In this implementation, the side where the dialysate flows into the dialyzer through the dialysate loop is the liquid supply end, and the side where the dialysate flows out of the dialyzer through the dialysate loop is the liquid return end. The detection module is installed on a single pump machine. After the detection module obtains the liquid return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient of the dialysate loop, the above data is sent to the main control module through circuit transmission. The main control module has a processor that can calculate the blood chamber pressure drop based on the liquid return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient.

[0039] In a possible implementation, the main control module calculates the blood chamber pressure drop based on the return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient as shown in Formula 1:

[0040] PB = (PDo + PDo + K*F d ) - 2PV (Formula 1)

[0041] Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, PDo is the pressure value at the return end, K is the pressure difference coefficient of the dialysate, and F d is the dialysis flow rate.

[0042] In this implementation, the main control module stores a calculation formula as shown in Formula 1. After receiving the information transmitted by the detection module through the circuit, the main control module has a processor, which can automatically run the relevant calculation program to calculate the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient data.

[0043] In a possible implementation, the HD single pump machine also includes an ultrafiltration pump, which is located at the return end of the dialysate circuit; the main control module is used to make the dialysate pressure value on the outside of the semipermeable membrane equal to the blood chamber pressure value on the inside of the semipermeable membrane, including: the main control module is used to control the ultrafiltration pump to pause operation, so that the dialysate pressure value on the outside of the semipermeable membrane is equal to the blood chamber pressure value on the inside of the semipermeable membrane.

[0044] In this implementation, the ultrafiltration pump is used to adjust the pressure in the dialysate circuit and drive the dialysate to circulate in the circuit. The main control module is electrically connected to the ultrafiltration pump, so as to control the normal operation or suspension of the ultrafiltration pump through electronic signals. When the main control module controls the ultrafiltration pump to suspend operation, the dialysate pressure in the dialysate circuit is no longer disturbed by the additional pressure applied by the ultrafiltration pump, but is only affected by the static pressure. At this time, based on the physical properties of the semipermeable membrane, the dialysate pressure on the outside of the semipermeable membrane will gradually converge with the blood chamber pressure on the inside of the semipermeable membrane, and finally reach a dynamic pressure balance between the inside and outside of the semipermeable membrane, so that the dialysate pressure value on the outside of the semipermeable membrane is equal to the blood chamber pressure value on the inside of the semipermeable membrane.

[0045] In one possible implementation, after the main control module automatically runs the relevant calculation program to calculate the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient data, the main control module controls the ultrafiltration pump to resume operation through an electronic signal so that the dialyzer continues to perform hemodialysis.

[0046] In a possible implementation, the main control module also includes a touch screen, wherein: the main control module receives preset touch instructions through the touch screen, thereby controlling the ultrafiltration pump and / or the detection module based on the touch instructions; the touch screen is also used to display the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow, the dialysate pressure difference coefficient and the blood chamber pressure drop.

[0047] In this implementation, an operation interface is displayed on the touch screen, and the user can interact with the touch screen through touch commands such as clicking and sliding, so that the main control module controls the normal operation or suspension of the ultrafiltration pump based on the touch command, or controls the detection module to detect the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient. This implementation allows the user to more conveniently control the detection process of the blood chamber pressure drop of the HD single pump machine, increasing the ease of use and practicality of the HD single pump machine. In addition, the touch screen can also display the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate, the dialysate pressure difference coefficient and the blood chamber pressure drop received by the main control module in real time, which is convenient for the user to monitor the use of the HD single pump machine.

[0048] In a possible implementation, the main control module is also used to store data, wherein: when the main control module completes a detection of the blood chamber pressure drop, the main control module stores the time of the detection, and stores the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow, the dialysate pressure difference coefficient and the blood chamber pressure drop in the detection.

[0049] In this implementation, the main control module controls the ultrafiltration pump to suspend operation, so that the dialysate pressure value on the outside of the semipermeable membrane is equal to the blood chamber pressure value on the inside of the semipermeable membrane, and then the blood chamber pressure drop is calculated based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient. Finally, the process of controlling the ultrafiltration pump to resume operation is regarded as a detection of the blood chamber pressure drop. This implementation enables the main control module to record the historical operation of the HD single pump machine by storing the time and related detection data of each blood chamber pressure drop detection. By viewing the stored data, the user can understand the operation of the HD single pump machine at different times, thereby enhancing the scope of application of the HD single pump machine.

[0050] In one possible implementation, the detection module includes a dialysate pressure sensor and a venous pressure sensor, wherein: the dialysate pressure sensor is located at the return end of the dialysate circuit, and is electrically connected to the main control module, for obtaining the return end pressure value, and sending the return end pressure value to the main control module; the venous pressure sensor is located at the outlet end of the blood chamber, and is electrically connected to the main control module, for obtaining the blood chamber outlet pressure value, and sending the blood chamber outlet pressure value to the main control module.

[0051] In this implementation, the side where the dialysate flows into the dialyzer through the dialysate circuit is the liquid supply end, and the side where the dialysate flows out of the dialyzer through the dialysate circuit is the liquid return end. The dialysate pressure sensor is installed at the liquid return end of the dialysate circuit, and detects the dialysate pressure value at the liquid return end, thereby transmitting the pressure data at the liquid return end to the main control module through the circuit. In the medical field, the pressure at the inlet end of the blood chamber is also called the filter pre-pressure, and the pressure value at the outlet end of the blood chamber is also called the venous pressure. The venous pressure sensor is installed at the outlet end of the blood chamber, and detects the blood pressure value at the outlet end of the blood chamber, thereby transmitting the pressure data at the outlet end of the blood chamber to the main control module through the circuit. The installation positions of the dialysate pressure sensor and the venous pressure sensor are far away from the blood pump at the inlet end of the dialyzer blood chamber, and their detection accuracy will not be disturbed by the blood pump.

[0052] A method for detecting blood chamber pressure drop of a HD single-pump machine and a HD single-pump machine provided by the present invention have at least the following advantages over the prior art:

[0053] The above-mentioned method for detecting blood chamber pressure drop of a single-pump HD machine is to make the dialysate pressure value on the outside of the semipermeable membrane equal to the blood chamber pressure value on the inside of the semipermeable membrane when the single-pump dialyzer performs hemodialysis. On the basis of this condition, the present invention obtains the return end pressure value, dialysis flow rate and dialysate pressure difference coefficient of the dialysate circuit on the outside of the semipermeable membrane, and obtains the pressure value of the blood chamber outlet end on the inside of the semipermeable membrane, and indirectly obtains the blood chamber pressure drop on the inside of the semipermeable membrane using the data on the outside of the semipermeable membrane, so that when the single-pump machine lacks a pressure sensor for detecting the blood chamber inlet end and cannot obtain the pressure value at the blood chamber inlet end, the blood chamber pressure drop is detected, solving the technical problem that the existing HD single-pump machine cannot detect the blood chamber pressure drop. In addition, the present invention can complete the detection of the blood chamber pressure drop by only using the existing equipment conditions of the HD single-pump machine, and does not need to install an additional pressure sensor at the blood chamber inlet end of the dialyzer.

[0054] The existing HD single pump machine is irreplaceable for the medical treatment it is applicable to. Adding an additional pressure sensor to the existing HD single pump machine is not only difficult to implement, but also has poor results. It may also destroy the original streamlined structure of the existing HD single pump machine, resulting in poor technical effects. On this basis, the present invention can complete the detection of blood chamber pressure drop using only the existing equipment conditions of the HD single pump machine, and does not require an additional pressure sensor to be installed at the inlet end of the dialyzer blood chamber. It is easy to promote and use in this field and has outstanding practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a flow chart of a method for detecting blood chamber pressure drop of a single HD pump machine provided by an embodiment of the present invention;

[0056] Figure 2 It is a schematic diagram of the pressure change of blood from flowing into the dialyzer blood chamber to flowing out of the dialyzer blood chamber provided by an embodiment of the present invention;

[0057] Figure 3 is a schematic diagram of the pressure change of the dialysate from flowing into the dialyzer to flowing out of the dialyzer provided by an embodiment of the present invention;

[0058] Figure 4 It is a structural diagram of a HD single pump machine provided by an embodiment of the present invention;

[0059] Figure 5 It is a circuit structure diagram of a HD single pump machine provided by an embodiment of the present invention;

[0060] Among them: 1. Dialysate circuit; 11. Liquid supply valve; 12. Liquid return valve; 13. Ultrafiltration pump; 14. Balance chamber; 2. Blood circuit; 21. Venous pot; 22. Blood pump; 23. Arterial pot; 3. Dialyzer; 4. Main control module; 41. Touch screen; 5. Detection module; 51. Dialysate pressure sensor; 52. Venous pressure sensor. DETAILED DESCRIPTION

[0061] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0062] The following detailed descriptions are all exemplary descriptions, and are intended to provide further detailed descriptions of the present invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments, and are not intended to limit the present application; the terms "including" and "having" in the specification and claims of the present application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of the present application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0063] It should be understood that, although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least a part of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a part of the sub-steps or stages of other steps.

[0064] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0065] See also Figure 1 The embodiment of the present invention provides a method for detecting blood chamber pressure drop of a single HD pump machine, wherein the single HD pump machine comprises a dialyzer, a dialysate circuit and a blood circuit, wherein the dialyzer comprises a semipermeable membrane, wherein the dialysate circuit flows through the outer side of the semipermeable membrane, wherein the inner side of the semipermeable membrane is a blood chamber, wherein the blood circuit flows through the blood chamber, and wherein the method comprises the following steps:

[0066] S101. When the dialyzer performs hemodialysis, the dialysate pressure value on the outer side of the semipermeable membrane is set equal to the blood chamber pressure value on the inner side of the semipermeable membrane.

[0067] S102, obtaining the return end pressure value of the dialysate loop, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient.

[0068] S103, calculating the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient, and taking the blood chamber pressure drop as the detection result.

[0069] In a possible implementation, the specific calculation formula for obtaining the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient is the following formula 1:

[0070] PB = (PDo + PDo + K*F d ) - 2PV (Formula 1)

[0071] Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, PDo is the pressure value at the return end, K is the pressure difference coefficient of the dialysate, and F d is the dialysis flow rate.

[0072] It should be noted that the blood chamber pressure drop specifically refers to the blood chamber inlet pressure value minus the blood chamber outlet pressure value. In the medical field, the blood chamber inlet pressure is also called the filter pre-pressure, and the blood chamber outlet pressure value is also called the venous pressure. Therefore, the dialyzer blood chamber pressure drop can also be described as equal to the filter pre-pressure minus the venous pressure, which can be expressed by the following formula 2:

[0073] PB = PA - PV (Formula 2)

[0074] Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, and PA is the pressure value at the inlet of the blood chamber.

[0075] See also Figure 2 For the blood circuit flowing through the blood chamber, since there is resistance in the blood circuit, the pressure of blood flowing out of the dialyzer blood chamber will be lower than the pressure when it flows into the dialyzer blood chamber, that is, the pressure at the blood chamber outlet is lower than the pressure at the blood chamber inlet, and this pressure drop process is a linear drop process. Therefore, the blood chamber pressure value inside the dialyzer semipermeable membrane is equal to the average of the blood chamber inlet pressure value and the blood chamber outlet pressure value, which can be expressed as the following formula 3:

[0076] Pb = (PA + PV) / 2 (Formula 3)

[0077] Wherein, Pb is the pressure value of the blood chamber, PA is the pressure value at the inlet end of the blood chamber, and PV is the pressure value at the outlet end of the blood chamber.

[0078] It should also be noted that in the medical field, the end of the dialysate loop in the HD single pump machine that flows into the dialyzer has a liquid supply valve, which can be called the liquid supply end, and the end of the dialysate loop that flows out of the dialyzer has a liquid return valve, which can be called the liquid return end. For the pressure value of the liquid supply end and the pressure value of the liquid return end, there is a mathematical relationship as shown in the following formula 4:

[0079] Pn = PDi - PDo = K*F d (Formula 4)

[0080] Wherein, Pn is the pressure difference between the dialysate flowing into the dialyzer and flowing out of the dialyzer, that is, the pressure difference between the supply end and the return end, PDi is the pressure value at the supply end, PDo is the pressure value at the return end, K is the dialysate pressure difference coefficient, F d is the dialysis flow rate.

[0081] See also Figure 3 For the dialysate loop flowing through the outside of the semipermeable membrane, since there is also resistance in the process of dialysate flowing in the dialysate loop, the pressure of the dialysate when it flows out of the dialyzer will be lower than the pressure when it flows into the dialyzer, that is, the pressure at the return end of the dialysate loop is lower than the pressure at the supply end of the dialysate loop, and this pressure drop process is a linear drop process. Therefore, the dialysate pressure value outside the dialyzer semipermeable membrane is equal to the average of the pressure value at the supply end and the pressure value at the return end, which can be expressed as the following formula 5:

[0082] Pd = (PDi + PDo) / 2 (Formula 5)

[0083] Among them, Pd is the dialysate pressure value outside the semipermeable membrane, PDi is the pressure value at the supply end, and PDo is the pressure value at the return end.

[0084] In this implementation, by making the dialysate pressure value Pd outside the semipermeable membrane equal to the blood chamber pressure value Pb inside the semipermeable membrane, the physical quantities in the HD single pump machine at this moment have the physical relationship described in the following formula 6:

[0085] Pb = ( PA + PV ) / 2 = Pd = ( PDi + PDo ) / 2 (Equation 6)

[0086] Among them, Pb is the blood chamber pressure value, PA is the blood chamber inlet pressure value, PV is the blood chamber outlet pressure value, Pd is the dialysate pressure value outside the semipermeable membrane, PDi is the pressure value at the supply end, and PDo is the pressure value at the return end. On this basis, the physical relationship of Formula 6, Formula 4 and Formula 2 is combined to obtain the physical calculation formula shown in Formula 1. Through the above technical means, this implementation method does not need to obtain the blood chamber inlet pressure value to detect the blood chamber pressure drop at the current moment, which solves the technical problem that the existing HD single pump machine cannot detect the blood chamber pressure drop, and does not need to install an additional pressure sensor at the dialyzer blood chamber inlet, which is easy to promote and use in this field.

[0087] See also Figure 4 and Figure 5 An embodiment of the present invention provides an HD single pump machine, including a dialysate circuit 1, a liquid supply valve 11, a liquid return valve 12, a balancing chamber 14, a blood circuit 2, a venous pot 21, a blood pump 22, an arterial pot 23, a dialyzer 3, a main control module 4, and a detection module 5.

[0088] Wherein: the dialyzer 3 is used for hemodialysis, which includes a semipermeable membrane, the dialysate circuit 1 flows through the outer side of the semipermeable membrane, the inner side of the semipermeable membrane is a blood chamber, and the blood circuit 2 flows through the blood chamber; the liquid supply valve 11 is located at the liquid supply end of the dialysate circuit 1, and the liquid supply valve 11 is electrically connected to the main control module 4, and is used to control the opening or closing of the liquid supply end of the dialysate circuit 1; the liquid return valve 12 is located at the liquid return end of the dialysate circuit 1, and the liquid return valve 12 is electrically connected to the main control module 4, and is used to control the opening or closing of the liquid return end of the dialysate circuit 1; the balancing chamber 14 is electrically connected to the main control module 4, and is used to control the dialysis flow of the dialysate circuit 1; the venous pot 21 is used to capture tiny bubbles remaining in the blood to prevent the bubbles from flowing back into the patient's body; the blood pump 22 is electrically connected to the main control module, and is used to adjust the pressure in the blood circuit to promote the blood to circulate in the blood circuit; the arterial pot 23 is used to reduce the eddy current and turbulence of arterial blood, and ensure that the blood enters the dialyzer at a steady flow rate; the detection module 5 is electrically connected to the main control module 4, and is used to obtain the return end pressure value of the dialysate circuit, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient and send them to the main control module 4; the main control module 4 is used to control the opening or closing of the liquid supply valve 11 and the liquid return valve 12. When the main control module 4 controls the liquid supply valve 11 and the liquid return valve 12 to open, the dialysate in the dialysate circuit 1 can flow through the dialyzer 3, thereby circulating in the dialysate circuit. The main control module 4 is also used to control the balancing chamber 15, thereby controlling the dialysis flow rate in the dialysate circuit 1. The main control module 4 is also used to control the normal operation of the blood pump 22, thereby adjusting the pressure in the blood circuit and promoting the blood to circulate in the blood circuit. The main control module 4 is used to make the dialysate pressure value outside the semipermeable membrane equal to the blood chamber pressure value inside the semipermeable membrane, and then calculate the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient.

[0089] In this embodiment, the side where the dialysate flows into the dialyzer 3 through the dialysate circuit 1 is the liquid supply end, and the side where the dialysate flows out of the dialyzer 3 through the dialysate circuit 1 is the liquid return end. The detection module 5 is installed on the single pump machine. After the detection module 5 obtains the liquid return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient of the dialysate circuit 1, the above data is sent to the main control module 4 through circuit transmission. The main control module 4 has a processor, which can calculate the blood chamber pressure drop based on the liquid return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient.

[0090] In a possible embodiment, the main control module 4 calculates the blood chamber pressure drop based on the return end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient as shown in Formula 1:

[0091] PB = (PDo + PDo + K*F d ) - 2PV (Formula 1)

[0092] Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, PDo is the pressure value at the return end, K is the pressure difference coefficient of the dialysate, and F d is the dialysis flow rate.

[0093] In this implementation, the main control module 4 stores a calculation formula as shown in Formula 1. After receiving the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient data transmitted by the detection module 5 through the circuit, the main control module 4 automatically runs the relevant calculation program through its processor to calculate the blood chamber pressure drop.

[0094] See also Figure 4 and Figure 5 In a possible embodiment, the HD single pump machine also includes an ultrafiltration pump 13, and the ultrafiltration pump 13 is located at the return end of the dialysate circuit 1; the main control module 4 is used to make the dialysate pressure value outside the semipermeable membrane equal to the blood chamber pressure value inside the semipermeable membrane, including: the main control module is used to control the ultrafiltration pump 13 to suspend operation, so that the dialysate pressure value outside the semipermeable membrane is equal to the blood chamber pressure value inside the semipermeable membrane.

[0095] In this embodiment, the ultrafiltration pump 13 is used to adjust the pressure in the dialysate circuit 1, driving the dialysate to circulate in the circuit. The main control module 4 is electrically connected to the ultrafiltration pump 13, so as to control the normal operation or suspension of the ultrafiltration pump 13 through electronic signals. When the main control module 4 controls the ultrafiltration pump 13 to suspend operation, the dialysate pressure in the dialysate circuit 1 is no longer disturbed by the additional pressure applied by the ultrafiltration pump 13, and is only affected by the static pressure. At this time, based on the physical properties of the semipermeable membrane, the dialysate pressure outside the semipermeable membrane will gradually converge with the blood chamber pressure inside the semipermeable membrane, and finally reach a dynamic pressure balance between the inside and outside of the semipermeable membrane, so that the dialysate pressure value outside the semipermeable membrane is equal to the blood chamber pressure value inside the semipermeable membrane.

[0096] In a possible embodiment, after the main control module 4 automatically runs the relevant calculation program to calculate the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient data, the main control module 4 controls the ultrafiltration pump 13 to resume operation through an electronic signal so that the dialyzer continues to perform hemodialysis.

[0097] See also Figure 4 and Figure 5 In a possible embodiment, the main control module also includes a touch screen 41, wherein: the main control module 4 receives preset touch instructions through the touch screen 41, thereby controlling the ultrafiltration pump 13 and / or the detection module 5 based on the touch instructions; the touch screen 41 is also used to display the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate, the dialysate pressure difference coefficient and the blood chamber pressure drop.

[0098] In this embodiment, an operation interface is displayed on the touch screen 41, and the user can interact with the touch screen through touch commands such as clicking and sliding, so that the main control module 4 controls the normal operation or suspension of the ultrafiltration pump 13 based on the touch command, or controls the detection module 5 to detect the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient. This implementation method allows the user to more conveniently control the detection process of the blood chamber pressure drop of the HD single pump machine, increasing the ease of use and practicality of the HD single pump machine. In addition, the touch screen 41 can also display the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate, the dialysate pressure difference coefficient and the blood chamber pressure drop received by the main control module 4 in real time, which is convenient for the user to monitor the use of the HD single pump machine.

[0099] In a possible embodiment, the main control module 4 is also used to store data, wherein: when the main control module 4 completes a detection of the blood chamber pressure drop, the main control module 4 stores the time of the detection, and stores the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow, the dialysate pressure difference coefficient and the blood chamber pressure drop in the detection.

[0100] In this embodiment, the main control module 4 controls the ultrafiltration pump 13 to suspend operation, so that the dialysate pressure value on the outside of the semipermeable membrane is equal to the blood chamber pressure value on the inside of the semipermeable membrane, and then the blood chamber pressure drop is calculated based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient, and finally the process of controlling the ultrafiltration pump 13 to resume operation is regarded as a detection of the blood chamber pressure drop. This implementation method enables the main control module 4 to record the historical operation of the HD single pump machine by storing the time and related detection data of each blood chamber pressure drop detection. By viewing the stored data, the user can understand the operation of the HD single pump machine at different times, thereby enhancing the scope of application of the HD single pump machine.

[0101] See also Figure 4 and Figure 5 In a possible embodiment, the detection module 5 includes a dialysate pressure sensor 51 and a venous pressure sensor 52, wherein: the dialysate pressure sensor 51 is located at the return end of the dialysate circuit 1, and is electrically connected to the main control module 4, for obtaining the return end pressure value, and sending the return end pressure value to the main control module 4; the venous pressure sensor 52 is located at the outlet end of the blood chamber, and is electrically connected to the main control module 4, for obtaining the blood chamber outlet pressure value, and sending the blood chamber outlet pressure value to the main control module 4.

[0102] In this embodiment, the side where the dialysate flows into the dialyzer 3 through the dialysate circuit 1 is the liquid supply end, and the side where the dialysate flows out of the dialyzer 3 through the dialysate circuit 1 is the liquid return end. The dialysate pressure sensor 51 is installed at the liquid return end of the dialysate circuit 1, and detects the dialysate pressure value at the liquid return end, thereby transmitting the pressure data of the liquid return end to the main control module 4 through the circuit. In the medical field, the pressure at the inlet end of the blood chamber is also called the filter pre-pressure, and the pressure value at the outlet end of the blood chamber is also called the venous pressure. The venous pressure sensor 52 is installed at the outlet end of the blood chamber, and detects the blood pressure value at the outlet end of the blood chamber, thereby transmitting the pressure data of the outlet end of the blood chamber to the main control module 4 through the circuit. The installation positions of the dialysate pressure sensor 51 and the venous pressure sensor 52 are far away from the blood pump at the inlet end of the blood chamber of the dialyzer 3, and their detection accuracy will not be disturbed by the blood pump.

[0103] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0104] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope recorded in this specification.

[0105] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present application. It should be noted that, for a person of ordinary skill in the art, several improvements and substitutions may be made without departing from the concept of the present application, and these improvements and substitutions shall also be regarded as the protection scope of the present invention. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for detecting blood chamber pressure drop of a single HD pump machine, wherein the single HD pump machine comprises a dialyzer, a dialysate circuit and a blood circuit, wherein the dialyzer comprises a semipermeable membrane, wherein the dialysate circuit flows through the outer side of the semipermeable membrane, wherein the inner side of the semipermeable membrane is a blood chamber, wherein the blood circuit flows through the blood chamber, wherein: The following steps are involved: When the dialyzer performs hemodialysis, the dialysate pressure value outside the semipermeable membrane is made equal to the blood chamber pressure value inside the semipermeable membrane; Obtaining the return end pressure value of the dialysate loop, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient; The blood chamber pressure drop is calculated based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient, and the blood chamber pressure drop is used as the detection result.

2. A method for detecting blood chamber pressure drop of a single HD pump machine according to claim 1, characterized in that: The specific calculation formula for calculating the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient is: PB=(PDo+PDo+K*F d )-2PV; Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, PDo is the pressure value at the return end, K is the pressure difference coefficient of the dialysate, and F d is the dialysis flow rate.

3. A method for detecting blood chamber pressure drop of a HD single pump machine according to claim 1, wherein the HD single pump machine further comprises an ultrafiltration pump, and the ultrafiltration pump is located at the return end of the dialysate loop, characterized in that: When the dialyzer performs hemodialysis, the dialysate pressure value outside the semipermeable membrane is made equal to the blood chamber pressure value inside the semipermeable membrane, including: The ultrafiltration pump is controlled to stop running, so that the dialysate pressure value outside the semipermeable membrane is equal to the blood chamber pressure value inside the semipermeable membrane.

4. A method for detecting blood chamber pressure drop of a HD single pump machine according to claim 3, characterized in that: The blood chamber pressure drop is calculated based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient, and after the blood chamber pressure drop is used as the detection result, the method further includes: The ultrafiltration pump is controlled to resume operation so that the dialyzer continues to perform hemodialysis.

5. A HD single pump machine, characterized in that: It includes a dialyzer, a dialysate circuit, a blood circuit, a detection module and a main control module, wherein: The dialyzer is used for hemodialysis, and comprises a semipermeable membrane, the dialysate circuit flows through the outer side of the semipermeable membrane, the inner side of the semipermeable membrane is a blood chamber, and the blood circuit flows through the blood chamber; The detection module is electrically connected to the main control module, and is used to obtain the return end pressure value of the dialysate loop, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient and send them to the main control module; The main control module is used to make the dialysate pressure value outside the semipermeable membrane equal to the blood chamber pressure value inside the semipermeable membrane, and then calculate the blood chamber pressure drop based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient.

6. The HD single pump machine according to claim 5, characterized in that: The specific calculation formula for the blood chamber pressure drop calculated by the main control module based on the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate and the dialysate pressure difference coefficient is: PB=(PDo+PDo+K*F d )-2PV; Wherein, PB is the pressure drop of the blood chamber, PV is the pressure value at the outlet of the blood chamber, PDo is the pressure value at the return end, K is the pressure difference coefficient of the dialysate, and F d is the dialysis flow rate.

7. The HD single pump machine according to claim 5, characterized in that: It also includes an ultrafiltration pump, which is located at the return end of the dialysate loop; the main control module is used to make the dialysate pressure value outside the semipermeable membrane equal to the blood chamber pressure value inside the semipermeable membrane, including: The main control module is used to control the ultrafiltration pump to stop running, so that the dialysate pressure value outside the semipermeable membrane is equal to the blood chamber pressure value inside the semipermeable membrane.

8. The HD single pump machine according to claim 7, characterized in that: The main control module also includes a touch screen, wherein: The main control module receives preset touch control instructions through the touch screen, thereby controlling the ultrafiltration pump and / or the detection module based on the touch control instructions; The touch screen is also used to display the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate, the dialysate pressure difference coefficient and the blood chamber pressure drop.

9. The HD single pump machine according to claim 5, characterized in that: The main control module is also used to store data, wherein: When the main control module completes a detection of the blood chamber pressure drop, the main control module stores the time of the detection, and stores the return liquid end pressure value, the blood chamber outlet end pressure value, the dialysis flow rate, the dialysate pressure difference coefficient and the blood chamber pressure drop in the detection.

10. The HD single pump machine according to claim 5, characterized in that: The detection module includes a dialysate pressure sensor and a venous pressure sensor, wherein: The dialysate pressure sensor is located at the return end of the dialysate loop and is electrically connected to the main control module, and is used to obtain the return end pressure value and send the return end pressure value to the main control module; The venous pressure sensor is located at the outlet of the blood chamber and is electrically connected to the main control module for obtaining the pressure value at the outlet of the blood chamber and sending the pressure value at the outlet of the blood chamber to the main control module.

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